Semiconductor devices and methods of manufacturing the same

CROSS-REFERENCE TO RELATED APPLICATION

0001This application is a continuation application of U.S. Ser. No. 14/326,760 filed on Jul. 9, 2014, which is a divisional application of U.S. Ser. No. 13/241,324 filed on Sep. 23, 2011, which claims priority from Korean Patent Application No. 10-2010-0108669 filed on Nov. 3, 2010 in the Korean Intellectual Property Office, and all the benefits accruing therefrom under 35 U.S.C. 119, the contents of which in their entirety are herein incorporated by reference.

BACKGROUND

0002A recent trend toward high integration of semiconductor devices uses a gate electrode of a memory device that occupies an increasingly smaller space. In this regard, the width and contact area of the gate electrode may be gradually reduced. Accordingly, contact resistance and sheet resistance of the gate electrode tend to increase, which may undesirably lower the operating speed. Therefore, a salicide (self-aligned silicide) process in which a metal gate is employed in order to reduce the resistance has been studied and developed.

0003However, since a highly integrated semiconductor device may have a reduced gate line width compared to a height of the gate electrode, it may not be easy to deposit the metal material during the salicide process. In addition, in a case where the metal gate and the salicide process are both employed, the metal gate may be dissolved in a wet-etching solution used in the salicide process or a metal stripping material. As such the metal gate may be damaged. Further, the more highly integrated the semiconductor device, the smaller the manufacturing margin thereof. Thus, in a case where misalignment occurs during the salicide process, a probability of the metal gate being damage may be increased.

SUMMARY

0004Some embodiments of the present invention provide semiconductor devices, which can facilitate a salicide process and can reduce or prevent damage to a gate due to misalignment.

0005Some embodiments of the present invention provide methods of manufacturing of semiconductor devices.

0006These and other objects of the present inventive concept will be described in or be apparent from the following description.

0007According to an aspect of the present disclosure, methods of manufacturing of a semiconductor device may include forming a first insulation layer pattern on a substrate having a gate pattern and a source/drain region formed at both sides of the gate pattern, the first insulation layer pattern having an exposed portion of the source/drain region. Operations may include forming a silicide layer on the exposed source/drain region, forming a second insulation layer on the entire surface of the substrate to cover the first insulation layer pattern and the silicide layer, and forming a contact hole in the second insulation layer to expose the silicide layer.

0008Some embodiments provide that methods of manufacturing a semiconductor device may include forming on a substrate a dummy gate pattern and source/drain region formed at both sides of the gate pattern, forming a passivation layer on the dummy gate pattern and the source/drain region, and removing the passivation layer to expose the dummy gate pattern and removing the exposed dummy gate pattern. Operations may further include forming a gate insulation layer and a metal layer on the entire surface of the substrate to cover a region having the dummy gate pattern removed therefrom and the passivation layer, and forming a metal gate pattern by performing planarization until the passivation layer is exposed. The passivation layer may be removed and a first insulation layer pattern may be formed on the entire surface of the substrate having a portion of the source/drain region exposed. Operations may further include forming a silicide layer on the exposed source/drain region, forming a second insulation layer pattern on the entire surface of the substrate to cover the first insulation layer pattern and the silicide layer, and forming a contact hole in the second insulation layer to expose the silicide layer.

0009In some embodiments, a semiconductor device includes a gate pattern including a gate insulation layer and a gate electrode formed on a substrate, a source/drain region formed at both sides of the gate pattern, a silicide layer formed on the source/drain region, a contact hole formed on the silicide layer, and an insulation layer formed on the gate pattern and the source/drain region and including the contact hole formed therein. Some embodiments provide that the gate pattern and the source/drain region have an aspect ratio of 3:1 or less.

0010In some embodiments, a semiconductor device may include a gate pattern including a gate insulation layer and a gate electrode formed on a substrate, a source/drain region formed at both sides of the gate pattern, a silicide layer formed on the source/drain region, a contact hole formed on the silicide layer; and an insulation layer formed on the gate pattern and the source/drain region and including the contact hole formed therein, wherein the gate pattern and the source/drain region have an aspect ratio of 3:1 or less.

0011As described above, in the methods disclosed herein, since a silicide layer is formed on a source/drain region before forming a contact hole, a difficulty with deposition of a metal during a salicide process performed after forming the contact hole can be overcome.

0012In addition, in the methods disclosed herein, it is possible to reduce or prevent damage to a metal gate due to misalignment during a salicide process.

0013Further, since the semiconductor devices disclosed herein may have a relatively small step difference between a source/drain region and a gate, which reduces an aspect ratio of a contact hole, efficiency of subsequent processes may be increased.

BRIEF DESCRIPTION OF THE DRAWINGS

0014The above and other features and advantages of the present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings in which:

0015<figref idref="DRAWINGS">FIG. 1</figref> is a cross-sectional view of a semiconductor device according to some embodiments disclosed herein;

0016<figref idref="DRAWINGS">FIG. 2</figref> is a cross-sectional view of a semiconductor device according to some embodiments disclosed herein;

0017<figref idref="DRAWINGS">FIG. 3</figref> is a flow chart illustrating operations corresponding to methods of manufacturing a semiconductor device according to some embodiments disclosed herein;

0018<figref idref="DRAWINGS">FIGS. 4A through 4G</figref> are cross-sectional views illustrating operations corresponding to methods of manufacturing a semiconductor device shown in <figref idref="DRAWINGS">FIG. 3</figref>;

0019<figref idref="DRAWINGS">FIG. 5</figref> is a flow chart illustrating operations corresponding to methods of manufacturing a semiconductor device according to some other embodiments disclosed herein; and

0020<figref idref="DRAWINGS">FIGS. 6A through 6N</figref> are cross-sectional views illustrating operations corresponding to methods of manufacturing a semiconductor device shown in <figref idref="DRAWINGS">FIG. 5</figref>.

DETAILED DESCRIPTION

0021Advantages and features of the present disclosure and methods of accomplishing the same may be understood more readily by reference to the following detailed description of preferred embodiments and the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concept of the invention to those skilled in the art, and the present invention will only be defined by the appended claims. In the drawings, the thickness of layers and regions are exaggerated for clarity.

0022It will be understood that when an element or layer is referred to as being “on,” or “connected to” another element or layer, it can be directly on or connected to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on” or “directly connected to” another element or layer, there are no intervening elements or layers present. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

0023It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, for example, a first element, a first component or a first section discussed below could be termed a second element, a second component or a second section without departing from the teachings of the present invention.

0024The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “made of,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

0025Embodiments described herein will be described referring to plan views and/or cross-sectional views by way of ideal schematic views of the invention. Accordingly, the example views may be modified depending on manufacturing technologies and/or tolerances. Therefore, the embodiments disclosed herein are not limited to those shown in the views, but include modifications in configuration formed on the basis of manufacturing processes. Therefore, regions exemplified in figures have schematic properties and shapes of regions shown in figures, exemplify specific shapes of regions of elements and do not limit aspects of the disclosure.

0026Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

0027Hereinafter, the embodiments disclosed herein will be described in further detail with reference to the accompanying drawings.

0028A semiconductor device according to some embodiments will now be described in more detail with reference to <figref idref="DRAWINGS">FIG. 1</figref>, which is a cross-sectional view of a semiconductor device according to some embodiments of the present disclosure.

0029Referring to <figref idref="DRAWINGS">FIG. 1</figref>, the semiconductor device <b>100</b> according to the illustrated embodiment includes a gate pattern <b>120</b>, a source/drain region <b>132</b>, a silicide layer <b>147</b>, a contact hole <b>151</b>, a first insulation layer <b>143</b> and a second insulation layer <b>148</b>. The semiconductor device <b>100</b> according to the illustrated embodiments may further include a gate spacer <b>124</b>.

0030The gate pattern <b>120</b> is formed on a substrate <b>110</b> and includes a gate insulation layer <b>120</b><i>a </i>and a gate electrode <b>120</b><i>b. </i>

0031The substrate <b>110</b> may be a silicon substrate, an SOI (Silicon On Insulator) substrate, a gallium arsenic substrate, a silicon germanium substrate, a ceramic substrate, a rigid substrate such as a quartz substrate or a glass substrate for a display, or a substrate made of a flexible plastic such as polyimide, polyester, polycarbonate, polyethersulfone, polymethylmethacrylate, polyethylenenaphthalate, and/or polyethyleneterephthalate, among others.

0032The gate insulation layer <b>120</b><i>a </i>may use a silicon oxide layer, SiON, Ge_xO_yN_z, Ge_xSi_yO_z, a highly dielectric material, combinations of these materials, and/or a stack of layers formed by sequentially stacking these materials. Here, the highly dielectric material is formed using HfO₂, ZrO₂, Al₂O₃, Ta₂O₅, hafnium silicate, zirconium silicate or a combination thereof but not limited thereto. <figref idref="DRAWINGS">FIG. 1</figref> illustrates a structure in which the gate insulation layer <b>120</b><i>a </i>surrounds sidewalls and a bottom of the gate electrode <b>120</b><i>b</i>, but a structure in which the gate electrode <b>120</b><i>b </i>is stacked on the gate insulation layer <b>120</b><i>a </i>may also be applied to embodiments disclosed herein.

0033The gate electrode <b>120</b><i>b </i>may be formed of a single film of poly-Si, poly-SiGe, impurity-doped poly-Si, a metal such as Ta, TaN, TaSiN, TiN, Mo, Ru, Ni, or NiSi, or metal silicide, or a stacked film of a combination of these materials, but not limited thereto. Some embodiments provide that the gate electrode <b>26</b> may be formed of a metal or metal silicide capable of implementing low resistance on a finer line width while not necessitating doping of impurities.

0034Although not shown in <figref idref="DRAWINGS">FIG. 1</figref>, a hard mask film that protects the gate electrode <b>120</b><i>b </i>may be formed on the gate electrode <b>120</b><i>b</i>. Here, the hard mask film may be formed of SiN or SiON.

0035The gate spacer <b>124</b> is formed on sidewalls of the gate insulation layer <b>120</b><i>a </i>and the gate electrode <b>120</b><i>b </i>to protect the gate electrode <b>120</b><i>b. </i>

0036The gate spacer <b>124</b> may include a first spacer <b>124</b><i>a </i>and a second spacer <b>124</b><i>b</i>. The first spacer <b>124</b><i>a </i>may be formed of a silicon oxide film, and the second spacer <b>124</b><i>b </i>may be formed of a silicon nitride film.

0037The source/drain region <b>132</b> is formed at both sides of the gate pattern <b>120</b>, respectively and may have an elevated structure in which the source/drain region <b>132</b> is elevated from the substrate <b>110</b>, thereby forming a junction having a constant depth. The elevated source and drain region structure is formed on a top surface of the substrate <b>110</b> having a penetration range (Rp) caused by impurity implementation, thereby obtaining a shallow junction structure. Accordingly, deterioration in the device characteristic due to a short channel effect can be improved.

0038The source/drain region <b>132</b> may be formed of an epitaxially grown silicon layer. Specifically, in order to suppress diffusion of impurities and improve mobility of carriers in a channel region, an NMOS is formed by implanting an impurity such as phosphorus (P) as an n-type dopant into Si or a SiC epitaxial layer, while a PMOS is formed by implanting an impurity such as boron (B) as an n-type dopant into a SiGe epitaxial layer. In addition, since the source/drain region <b>132</b> has a facet formed on upper side surface, a gap between the source/drain region <b>132</b> and the gate pattern <b>120</b> may be created at a portion where a facet of the source/drain region <b>132</b> is formed.

0039The gate pattern <b>120</b> and the source/drain region <b>132</b> may have an aspect ratio of 3:1 or less. In some embodiments, the aspect ratio refers to a ratio of a step difference between a top portion of the gate pattern <b>120</b> and a top portion of the source/drain region <b>132</b> to a width (b) of the source/drain region <b>132</b>. When the aspect ratio is 3:1 or less, uniform deposition may be achieved in a subsequent process. The gate pattern <b>120</b> and the source/drain region <b>132</b> may have a step difference of 250 Å or less from the substrate <b>110</b>. If the step difference between the gate pattern <b>120</b> and the source/drain region <b>132</b> is 250 Å or less, the aspect ratio may be reduced, thereby facilitating deposition in a subsequent deposition process performed on the gate pattern <b>120</b> and the source/drain region <b>132</b> and forming a uniformly deposited film.

0040The source/drain region <b>132</b> may be formed to have the same height as the gate pattern <b>120</b>. <figref idref="DRAWINGS">FIG. 1</figref> illustrates a structure in which the source/drain region <b>132</b> is elevated as high as the gate pattern <b>120</b>.

0041The silicide layer <b>147</b> is formed on the source/drain region <b>132</b> to reduce contact resistance. The silicide layer <b>147</b> may be formed by depositing a metal layer on the source/drain region <b>132</b> and reacting the metal layer with the source/drain region <b>132</b>, followed by removing the unreacted portion of the metal layer.

0042The silicide layer <b>147</b> may include Ni, Co, Pt or Ti, and may be formed by being permeated to the top portion of the source/drain region <b>132</b> to a predetermined depth. Alternatively, the silicide layer <b>147</b> may be formed on the source/drain region <b>132</b> to a predetermined height.

0043The first insulation layer <b>143</b> is formed on the gate pattern <b>120</b> and the source/drain region <b>132</b>. The first insulation layer <b>143</b> serves to planarize the surface of the substrate <b>110</b> having the gate pattern <b>120</b> and the source/drain region <b>132</b> while substantially completely covering the gate pattern <b>120</b> and the source/drain region <b>132</b>. In addition, the first insulation layer <b>143</b> serves to prevent the gate electrode from being damaged in a subsequent process by filling the gap by the facet of the source/drain region <b>132</b>. Further, the first insulation layer <b>143</b> may function as an etch stopper in an etching process of forming, for example, a contact hole <b>151</b>. Therefore, the first insulation layer <b>143</b> may be formed of a material having a different etch ratio from the second insulation layer <b>148</b>. Specifically, the first insulation layer <b>143</b> may be formed by a silicon oxide film, a silicon nitride film, or a double-layered structure of these films. The first insulation layer <b>143</b> may be formed by a silicon nitride film.

0044The second insulation layer <b>148</b> is formed on the first insulation layer <b>143</b>, and may be formed of, but is not limited to, a silicon oxide film, a silicon nitride film, or a multiple-layered structure of one or more of these films.

0045The contact hole <b>151</b> is formed in the first insulation layer <b>143</b> and the second insulation layer <b>148</b> to expose the predetermined region of the silicide layer <b>147</b>. In detail, since the contact hole <b>151</b> is formed on the silicide layer <b>147</b>, the silicide layer <b>147</b> is exposed at the bottom of the contact hole <b>151</b>, thereby reducing contact resistance while not necessitating separately forming a silicide layer in the bottom of the contact hole <b>151</b>. The contact hole <b>151</b> may be filled with a metal such as tungsten (W).

0046In the illustrated embodiments, the source/drain region <b>132</b> and the gate pattern <b>120</b> may have a relatively small step difference and the contact hole <b>151</b> is formed on the silicide layer <b>147</b>. Therefore, even if misalignment occurs during formation of the contact hole, it is possible to prevent the gate electrode from being damaged.

0047Next, a semiconductor device <b>200</b> according to other embodiments disclosed herein will be described with reference to <figref idref="DRAWINGS">FIG. 2</figref>, which is a cross-sectional view of a semiconductor device according to such embodiments.

0048The semiconductor device <b>200</b> is different from the semiconductor device <b>100</b> shown in <figref idref="DRAWINGS">FIG. 1</figref> in that it has a source and drain region <b>232</b> different from the corresponding portion of the previous embodiment in view of configuration, including a lightly doped source/drain region <b>211</b> and a heavily doped source/drain region <b>212</b>. Thus, the following description of the illustrated semiconductor device will focus on the differences from the previously described embodiments of <figref idref="DRAWINGS">FIG. 1</figref>. Accordingly, the same reference numerals will be used to refer to the same elements as those described in <figref idref="DRAWINGS">FIG. 1</figref>, and detailed explanation thereof may be omitted.

0049The source and drain regions <b>232</b> may be formed of an epitaxial layer formed in a trench formed by etching a predetermined area of the substrate <b>110</b>. In detail, a preliminary trench is formed in the substrate <b>110</b> and a trench for epitaxial formation is formed by further laterally etching sidewalls of the preliminary trench, followed by being subjected to epitaxial growth in the trench for epitaxial formation.

0050The trench for epitaxial formation may have a hexagonal profile, and the epitaxial layer may be a silicon layer or a silicon germanium (SiGe) layer formed by being subjected to epitaxial growth in the trench for epitaxial formation. The silicon germanium layer may increase current by applying a compressive stress to a channel region to increase the mobility of holes. A tip <b>213</b> corresponding to a portion of the trench having the maximum width may be positioned on the same line or may be aligned with the sidewalls of the gate pattern <b>120</b>. Since the silicon germanium layer formed in the trench for epitaxial formation is formed closer to the channel region, the compressive stress applied to the channel region is increased thereby further increasing the mobility of holes.

0051A top portion of the epitaxial layer may be formed higher than a top portion of the substrate. An aspect ratio of the source/drain region <b>232</b> formed of the epitaxial layer to gate pattern <b>120</b> may be 3:1 or less. In addition, the source and drain region <b>232</b> and the gate pattern <b>120</b> may have a step difference of 250 Å or less. Further, the epitaxial layer may be formed to have the same height as the gate pattern <b>120</b>.

0052The lightly doped source/drain region <b>211</b> and the heavily doped source/drain region <b>212</b> surround a peripheral portion of the trench, and the trench may be formed in the lightly doped source/drain region <b>211</b> and the heavily doped source/drain region <b>212</b>. A PMOS transistor may be formed using p-type impurity such as boron (B), and an NMOS transistor may be formed using n-type impurity such as phosphorus (P) or arsenic (As).

0053The lightly doped source/drain region <b>211</b> is formed by implanting impurity into the substrate in both sides of the gate pattern <b>120</b>, and the heavily doped source/drain region <b>212</b> is formed by implanting impurity into a lower portion of the lightly doped source/drain region <b>211</b> from both sides of the gate spacer <b>124</b>.

0054Hereinafter, methods of manufacturing a semiconductor device according to some embodiments disclosed herein will now be described with reference to <figref idref="DRAWINGS">FIGS. 3 and 4A through 4G</figref>. <figref idref="DRAWINGS">FIG. 3</figref> is a flow chart illustrating operations corresponding to methods of manufacturing a semiconductor device according to some embodiments herein, and <figref idref="DRAWINGS">FIGS. 4A through 4G</figref> are cross-sectional views illustrating operations of the methods of manufacturing a semiconductor device shown in <figref idref="DRAWINGS">FIG. 3</figref>.

0055Referring to <figref idref="DRAWINGS">FIG. 3</figref>, the methods of manufacturing a semiconductor device according to some embodiments include forming a first insulation layer pattern (block <b>10</b>), forming a silicide layer (block <b>20</b>), forming a second insulation layer (block <b>30</b>), forming a contact hole (block <b>40</b>), and filling (block <b>50</b>).

0056Referring to <figref idref="DRAWINGS">FIGS. 4A and 4B</figref>, a first insulation layer pattern <b>143</b> is formed on a substrate having a gate pattern <b>120</b> and a source/drain region <b>132</b> formed at both sides of the gate pattern <b>120</b> (<figref idref="DRAWINGS">FIG. 3</figref>, block <b>10</b>).

0057In detail, a first insulation layer <b>143</b>′ is deposited to cover the entire surface of the gate pattern <b>120</b> and the source/drain region <b>132</b>, a photoresist pattern <b>142</b> is formed on the first insulation layer <b>143</b>′, and a photolithography process is performed using the photoresist pattern <b>142</b> as an etch mask, thereby forming the first insulation layer pattern <b>143</b> having a predetermined exposed portion of the source/drain region <b>132</b>. The first insulation layer <b>143</b>′ may be formed of a silicon oxide film or a silicon nitride film.

0058Here, the gate pattern <b>120</b> may have a stacked structure in which the gate insulation layer <b>121</b>, the gate electrode <b>122</b> and the hard mask film <b>123</b> are sequentially stacked. In some embodiments, the hard mask film <b>123</b> may be omitted.

0059The gate spacer <b>124</b> having a single layered structure or a double layered structure may be formed on sidewalls of the gate pattern <b>120</b> and the gate electrode <b>120</b><i>b </i>to protect the gate electrode <b>120</b><i>b</i>. <figref idref="DRAWINGS">FIG. 4B</figref> illustrates that the gate spacer <b>124</b> has a double layered structure of an oxide film <b>124</b><i>a </i>and a nitride film <b>124</b><i>b. </i>

0060The source/drain region <b>132</b> may be formed at both sides of the gate pattern <b>120</b> to have a predetermined height so as to have a structure in which the source/drain region <b>132</b> is elevated from the surface of the substrate <b>110</b>. In addition, the source and drain region may be formed through epitaxial growth. Further, the source/drain region <b>132</b> may be an epitaxial silicon layer formed in the trench recessed into the substrate <b>110</b> to a predetermined depth.

0061Methods for forming the source/drain region of a PMOS transistor will now be described in more detail. First, a lightly doped source/drain region is formed by implanting low concentration impurity ions using the gate pattern as an etch mask, and then a gate spacer is formed, followed by implanting high-concentration impurity ions using the gate pattern and the gate spacer as etch masks, thereby forming a heavily doped source/drain region. Subsequently, a predetermined region of the substrate exposed by the gate pattern and the gate spacer is etched to form a trench, and a SiGe epitaxial layer is formed in the trench. Here, the trench may have a hexagonal profile, and the trench may be etched such that a tip of the trench having a maximum width is positioned on the same line with sidewalls of the gate pattern.

0062Here, the source/drain region <b>232</b> formed of an epitaxial layer and the gate pattern <b>120</b> may have an aspect ratio of 3:1 or less. In some embodiments, the source/drain region <b>232</b> and the gate pattern <b>120</b> may have a step difference of 250 Å or less. In some embodiments, a top portion of the gate pattern <b>120</b> and a top portion of the source/drain region <b>132</b> are positioned at the same height. Since the gate pattern <b>120</b> and the source/drain region <b>132</b> have a step difference of 250 Å or less, the aspect ratio thereof are reduced, thereby achieving uniform deposition of the first insulation layer <b>143</b>′.

0063Referring to <figref idref="DRAWINGS">FIGS. 4C and 4D</figref>, metal layers <b>144</b>, <b>145</b> and <b>146</b> are deposited on a predetermined portion of the source/drain region exposed in operations corresponding to block <b>10</b> and the first insulation layer pattern <b>143</b> to react with silicon of the source/drain region <b>132</b> to form the silicide layer <b>147</b> (<figref idref="DRAWINGS">FIG. 3</figref>, block <b>20</b>).

0064In detail, forming the silicide layer <b>147</b> may include forming a single layer or a multi-layered metal layers <b>144</b>, <b>145</b> and <b>146</b> containing Ni, Co, Pt, Ti or an alloy thereof on the exposed source/drain region and the first insulation layer pattern <b>143</b>. An annealing process is performed at a temperature of approximately 500 degrees C. to approximately 800 degrees C. to react the deposited metal with silicon of the source/drain region <b>132</b> and remove unreacted metal using an etching process, thereby forming the silicide layer <b>147</b>. That is to say, the silicide layer <b>147</b> of the illustrated embodiments may be formed through a salicide (self aligned silicide) process. The silicide layer <b>147</b> resulting from the reacting of the deposited metal layer with silicon may be permeated into the source/drain region <b>132</b>. While <figref idref="DRAWINGS">FIG. 4D</figref> illustrates that the silicide layer <b>147</b> is substantially completely permeated into the source/drain region <b>132</b>, the invention is not limited thereto and the silicide layer <b>147</b> may protrude toward the top portion of the source/drain region <b>132</b>.

0065In the illustrated embodiments, before forming a contact hole, the silicide layer <b>147</b> is formed on the source/drain region <b>132</b>. In a case where the silicide layer <b>147</b> is formed after forming the contact hole, a metal layer may not be uniformly deposited in the contact hole due to a large aspect ratio of the contact hole, making it difficult to form a sufficiently thick silicide layer. In the illustrated embodiments, however, the silicide layer may be formed before forming the contact hole and the gate pattern and the source/drain region may have a small aspect ratio. In this manner, a silicide layer having a uniform thickness may be formed. In addition, since the first insulation layer pattern <b>143</b> serves to protect a gate electrode, it is possible to reduce or prevent damage to the gate electrode when the unreacted metal is etched.

0066Referring to <figref idref="DRAWINGS">FIG. 4E</figref>, the second insulation layer <b>148</b> is formed on the silicide layer <b>147</b> and the first insulation layer pattern <b>143</b> (<figref idref="DRAWINGS">FIG. 3</figref>, block <b>30</b>). In detail, a silicon oxide film or a silicon nitride film substantially completely covering top surfaces of the silicide layer <b>147</b> and the first insulation layer pattern <b>143</b> is deposited, thereby forming the second insulation layer <b>148</b>. The first insulation layer <b>143</b>′ and the second insulation layer <b>148</b> may be made of different materials. Specifically, the first insulation layer <b>143</b>′ may be formed of a silicon nitride film, while the second insulation layer <b>148</b> may be formed of a silicon oxide film.

0067Referring to <figref idref="DRAWINGS">FIG. 4F</figref>, a contact hole <b>151</b> is formed on the silicide layer <b>147</b> (<figref idref="DRAWINGS">FIG. 3</figref>, block <b>40</b>). In detail, the contact hole <b>151</b> is formed by etching the second insulation layer <b>148</b> so as to expose the silicide layer <b>147</b>. The etching of the second insulation layer <b>148</b> may be performed by a method known in the art. Through the above-described process, the silicide layer <b>147</b> exists to a lower portion of the contact hole <b>151</b>, and it is not necessary to separately form a silicide layer in the contact hole <b>151</b>. In the process of etching the second insulation layer <b>148</b> in order to form the contact hole <b>151</b>, the first insulation layer <b>143</b>′ may be used as an etch stopper, thereby preventing the gate electrode <b>122</b> from being damaged.

0068Referring to <figref idref="DRAWINGS">FIG. 4G</figref>, a conductive material is filled in the contact hole <b>151</b> (<figref idref="DRAWINGS">FIG. 3</figref>, block <b>50</b>). In detail, the inside of the contact hole <b>151</b> is filled with a conductive material such as a metal, thereby forming a metal wire contact. Specifically, tungsten (W) may be used as the metal.

0069Reference is now made to <figref idref="DRAWINGS">FIG. 5</figref>, which is a flow chart illustrating operations corresponding to methods of manufacturing a semiconductor device according to some embodiments disclosed herein and to <figref idref="DRAWINGS">FIGS. 6A through 6N</figref>, which are cross-sectional views illustrating operations corresponding to the methods of manufacturing a semiconductor device shown in <figref idref="DRAWINGS">FIG. 5</figref>. For brevity of explanation, in the methods of manufacturing the semiconductor device according to the illustrated embodiments, portions that are the same as or similar to those of the method of manufacturing the semiconductor device according to the previous embodiment are denoted by the same reference numerals, and a detailed explanation thereof may be omitted. Accordingly, the following description of the illustrated semiconductor device will focus on the differences.

0070Referring to <figref idref="DRAWINGS">FIG. 5</figref>, operations include forming a dummy gate pattern and a gate spacer (block <b>1</b>), forming a source/drain region (block <b>2</b>), forming a passivation layer (block <b>3</b>), removing the dummy gate pattern (block <b>4</b>), forming a metal gate (block <b>5</b>) and removing the passivation layer (block <b>6</b>). In addition to, the methods of manufacturing the semiconductor device according to the illustrated embodiment of the present invention may further include steps of forming a first insulation layer pattern (block <b>10</b>), forming a silicide layer (block <b>20</b>), forming a second insulation layer (block <b>30</b>), forming a contact hole (block <b>40</b>) and filling (block <b>50</b>).

0071Referring to <figref idref="DRAWINGS">FIG. 6A</figref>, the dummy gate pattern <b>120</b> and the gate spacer <b>124</b> are formed on the substrate <b>110</b> (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>1</b>). In detail, a first insulation layer, a polysilicon layer, and a second insulation layer are sequentially stacked on the substrate <b>110</b> and patterned to form a dummy gate pattern <b>120</b> having a stacked structure in which the gate insulation layer <b>121</b>, the dummy gate <b>122</b> and the hard mask film <b>123</b> are sequentially stacked. Next, an insulation layer for a first spacer and an insulation layer for a second spacer are sequentially formed on sidewalls of the gate pattern <b>120</b> and etched to form a gate spacer <b>124</b>. The first spacer <b>124</b><i>a </i>is formed of a silicon oxide film, while the second spacer <b>124</b><i>b </i>may be formed of a silicon nitride film. Some embodiments provide that the hard mask film <b>123</b> may be omitted.

0072Referring to <figref idref="DRAWINGS">FIG. 6B</figref>, the source/drain region <b>132</b> is formed at both sides of the dummy gate pattern <b>120</b>, respectively (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>2</b>). In detail, the source/drain region <b>132</b> doped with impurity ions is formed at both sides of the gate pattern <b>120</b> through epitaxial growth, respectively. The epitaxial process for forming the source/drain region <b>132</b> may be performed at a temperature of approximately 500 degrees C. to about 900 degrees C. under approximately 1 to 500 torr using a selective epitaxial growth process such as a low pressure chemical vapor deposition (LPCVD), ultrahigh vacuum chemical vapor deposition (UHV-CVD), or the like, but may be appropriately adjusted within the scope of the present invention. The source/drain region <b>132</b> may be formed of an epitaxial layer such as Si, SiC or SiGe. In the epitaxial process, SiH₄, SiH₂Cl₂, SiHCl₃, SiCl₄, SiH_xCl_y(x+y=4), Si(OC₄H₉)₄, Si(OCH₃)₄, Si(OC₂H₅)₄, or the like, may be used as a silicon source material, GeH₄, GeCl₄, GeH_xCl_y(x+y=4), or the like, may be used as a germanium source material, and C_xH_y, CH₃SiH₃, or the like, and/or may be used as a carbon source material, among others. In order to improve selective characteristics, a gas such as HCl or Cl₂may also be added. Specifically, for the purpose of doping, a gas such as B₂H₆, PH₃, AsH₃, or the like may be added.

0073As shown in <figref idref="DRAWINGS">FIG. 6C</figref>, the source/drain region <b>232</b> of PMOS may be formed of an epitaxially grown silicon germanium layer. The silicon germanium layer is formed through epitaxial growth in a trench formed by etching a predetermined portion of the substrate <b>110</b>. The lightly doped source/drain region <b>211</b> and the heavily doped source/drain region <b>212</b> surround a peripheral portion of the trench, and the trench may have a hexagonal profile. A tip <b>213</b> of the trench may be positioned on the same line or aligned with sidewalls of the dummy gate pattern <b>120</b>.

0074In some embodiments, an aspect ratio of the source/drain region <b>132</b> to the dummy gate pattern <b>120</b> may be 3:1 or less. Some embodiments provide that the source/drain region <b>132</b> may be formed to have a step difference of 250 Å or less with respect to a top surface of the dummy gate pattern <b>120</b>. The smaller the step difference between the source/drain region <b>132</b> and the gate pattern <b>120</b>, the smaller the aspect ratio, thereby achieving substantially uniform deposition in a subsequent process.

0075Referring to <figref idref="DRAWINGS">FIG. 6D</figref>, a passivation layer <b>141</b> covering the gate pattern <b>120</b> and the source/drain region <b>132</b> is formed (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>3</b>). In detail, the passivation layer <b>141</b> that is an interlayer dielectric layer is formed on the entire surface of the substrate <b>110</b> to cover the gate pattern <b>120</b> and the source/drain region <b>132</b>. The passivation layer <b>141</b> may be formed of a silicon oxide film, a silicon nitride film, or a double layer of these films.

0076Referring to <figref idref="DRAWINGS">FIGS. 6E and 6F</figref>, the passivation layer <b>141</b> is removed to expose the dummy gate pattern <b>120</b> and the exposed dummy gate pattern <b>120</b> is removed to expose the substrate <b>110</b> (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>4</b>). In detail, the passivation layer <b>141</b> is polished by a chemical mechanical polishing (CMP) process to expose the dummy gate pattern <b>120</b> and the exposed dummy gate pattern <b>120</b> is removed by a selective etching process to expose the substrate <b>110</b>. In such a manner, a trench is formed in a region from which the dummy gate pattern <b>120</b> is removed.

0077<figref idref="DRAWINGS">FIGS. 6G and 6H</figref>, an insulation layer <b>125</b>′ and a metal layer <b>126</b>′ are sequentially stacked and planarized on the passivation layer <b>141</b> while filling the trench, thereby forming the gate insulation layer <b>125</b> and the metal gate <b>126</b> (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>5</b>). Specifically, the insulation layer <b>125</b>′ and the metal layer <b>126</b>′ are sequentially stacked in the trench formed after removing the passivation layer <b>141</b> and the dummy gate pattern <b>120</b>, and then planarized by etching the insulation layer <b>125</b>′ and the metal layer <b>126</b>′, thereby allowing the passivation layer <b>141</b> to be exposed. Here, since there is a small difference between the source/drain region <b>142</b> and the gate pattern <b>120</b>, the passivation layer <b>141</b> on the source/drain region <b>132</b> is substantially completely removed in the process of etching the passivation layer <b>141</b>, thereby achieving planarization so that the source/drain region <b>142</b> and the metal gate <b>126</b> have the same height from the substrate <b>110</b>. The insulation layer <b>125</b>′ may generally be formed a silicon oxide film or made of an insulating material such as Ta₂O₅, Al₂O₃, and the metal layer <b>126</b>′ may be made of tungsten (W), WN, Ti, TiN, Mo, and/or Ta, among others.

0078Through the above-described manner, a poly-gate electrode made of polysilicon is removed to form a metal gate. The metal gate may achieve low resistance in a finer line width than the poly-gate.

0079Referring to <figref idref="DRAWINGS">FIG. 6I</figref>, the passivation layer <b>141</b> remaining on the source/drain region <b>132</b> is removed (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>6</b>). In detail, a top portion of the source/drain region <b>132</b> is exposed by etching the exposed passivation layer <b>141</b>. Here, the passivation layer filling a gap created due to a facet of the source/drain region <b>132</b> is substantially completely removed.

0080<figref idref="DRAWINGS">FIG. 6J</figref> is a cross-sectional view illustrating forming a first insulation layer pattern (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>10</b>). <figref idref="DRAWINGS">FIG. 6K</figref> is a cross-sectional view illustrating forming a silicide layer (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>20</b>), <figref idref="DRAWINGS">FIG. 6L</figref> is a cross-sectional view illustrating forming a second insulation layer (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>30</b>), <figref idref="DRAWINGS">FIG. 6M</figref> is a cross-sectional view illustrating forming a contact hole (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>40</b>), and <figref idref="DRAWINGS">FIG. 6N</figref> is a cross-sectional view illustrating filling (<figref idref="DRAWINGS">FIG. 5</figref>, block <b>50</b>). Since the steps of forming a first insulation layer pattern (block <b>10</b>), forming a second insulation layer (block <b>30</b>), forming a contact hole (block <b>40</b>), and filling (block <b>50</b>) are substantially the same as those described in the methods of manufacturing a the semiconductor device according to previous embodiments, and a detailed description thereof will not be given.

0081In the methods of manufacturing the semiconductor device according to the illustrated embodiments disclosed herein, a step difference between the gate pattern and the source/drain region is small to reduce the aspect ratio, thereby obtaining a uniformly deposited film in a subsequent process. In addition, since a silicide layer is formed on the source/drain region before forming the contact hole, it is not necessary to form a separate silicide layer into the contact hole. Further, it is possible to reduce or prevent damage to the metal gate in a salicide process.

0082While the present disclosure has been particularly shown and described with reference to example embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by the following claims. It is therefore desired that the present embodiments be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than the foregoing description to indicate the scope of the disclosure.